(#12357) Make facter_dot_d look in Puppet[:confdir]/facts.d

(#12357) Make facter_dot_d look in Puppet[:confdir]/facts.d

On Windows, we have no folders that match up to the default set of
directories the facter_dot_d fact looks in by default.  This is a
problem because the Puppet Enterprise installer writes out the following
facts by default, and our modules require them to be present:

    % cat /etc/puppetlabs/facter/facts.d/puppet_enterprise_installer.txt
    fact_stomp_port=61613
    fact_stomp_server=puppetmaster
    fact_is_puppetagent=true
    fact_is_puppetmaster=true
    fact_is_puppetconsole=true

On windows, the Puppet confdir is quite variable.  On 2003 systems we
default to the All Users application data directory.  On 2008 systems we
default to the ProgramData directory.  The actual configuration
directory varies depending on the Puppet or Puppet Enterprise branding.

In order to simplify all of this variable behavior, this patch fixes the
problem by automatically looking for facts in
`%COMMON_APPDATA%/PuppetLabs/facter/facts.d`

This patch paves the way for the MSI installer to use an IniFile element
to write custom facts during installation.